51�Թ�

The interior of the box contains a maximum thermometer in vacuo for solar radiation, and a minimum for terrestrial purposes, one of Negretti and Zambra’s small pocket aneroid barometers, pedometer for measuring distances, pocket compass, clinometer, and lastly a rain gauge.

Of no other maximum thermometer can it be said that it is impossible to derange or put it out of order; hence, as regards durability, it surpasses all others.

A thermometer constructed to register the highest temperature is usually called a maximum thermometer; one to show the lowest temperature is termed a minimum thermometer; and if made to record both extremes of temperature, it is designated a maximum-and-minimum thermometer.

Phillip’s Maximum Thermometer.—A maximum thermometer, better perhaps in its action than Rutherford’s, has been suggested by Professor John Phillips, of Oxford.

This forms a maximum thermometer, when the stem is arranged horizontally.